Cryptology ePrint Archive: BibTeX Citation of Report 2004/052

@misc{cryptoeprint:2004:052,
    author = {Tal Malkin and Satoshi Obana and Moti Yung},
    title = {The Hierarchy of Key Evolving Signatures and a Characterization of Proxy Signatures},
    howpublished = {Cryptology ePrint Archive, Report 2004/052},
    year = {2004},
    note = {\url{http://eprint.iacr.org/}},
}

You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.